There’s the point at the beginning of every sci-fi film where the world and rules are explained; most plainly done, it’s delivered as a news broadcast, or an in-progress incident that gives context to the whole. If well depicted, we’re in and engaged as an audience, but how best to explain society and politics of the past few decades? “The Big Short” answers this question by treating early-‘00s Wall Street as an absurd alien horrorshow. It labors on explaining industry jargon, not because director Adam McKay believes we’re dumb, but because the seemingly benign terms being discussed hold the absurd, hilarious, and depressing truths about the 2008 global financial crisis within them — and he’s keen to depict them all.

In adapting “Moneyball” author Michael Lewis’s book of the same name, it’s clear McKay has achieved his “Inception” — a studio-backed reward after a string of comedic hits like “Anchorman” and “Step Brothers.” He dabbles in genuine irreverence, political energy, and a formal inventiveness here that is a delight to see, and a constant surprise. To be certain, it’s a drama first with laughs throughout, but few other political dramas this year will feature Jenga as a plot device, use celebrity cameos as pointed commentary (go in unspoiled), or soundtrack a scene with Mastodon followed by the theme from “Phantom of the Opera.”

Another stylistic choice felt straight away is to-camera narration, which of course instantly calls to mind “TheWolf Of Wall Street,” Martin Scorsese’s bacchanalian epic that tracked every facet of corruption imaginable. This takes a slowly diverging approach. As Ryan Gosling (playing fictional trader Jared Vennett) describes in the opening, the film is about the “weirdos” who stumbled upon the reality of Wall Street firms well before 2008: that they were obtaining insane wealth with porous subprime mortgages, all of which were falsely certified by a ratings agency pressured to comply.

Among the “weirdos” is Michael Burry (Christian Bale), the heavy metal-loving head of the Scion Capital hedge fund; funder Mark Baum (Steve Carell), eternally about to explode under a blonde haircut; and Charles Geller (John Magaro) and Jamie Shipley (Finn Wittrock), “garage band hedge fund” owners who implore former banker Ben Rickert (Brad Pitt) to help them get a seat at the Wall Street table. Once the idea to bet against the market enters the frame — profiting in the face of widespread devastation — each faction responds differently. Some celebrate, others panic, but it’s clear none can imagine what the actual result would look like in 2008.

The film stumbles out of the gate setting all this up, a gargantuan task for McKay and co-writer Charles Randolph’s adept screenplay. They establish a dozen characters, provide flashbacks for three of them, describe the 2005 financial landscape, and aim to do so with a handful of laughs. It’s an absolute bombardment, which McKay mirrors in his fast-paced editing choices and fly-on-the-wall cinematography by Barry Ackroyd. He also factors in a heavy amount of still images, animations, and archival footage of the relevant (real-life evictions) and otherwise (a Britney Spears interview for “Crossroads”).

Of the entire ensemble, only Carell’s character receives anywhere close to a fully-rounded treatment, mostly having to do with a past trauma and his relationship to his wife Cynthia (Marisa Tomei). The rest are very much foils and archetypes, as Gosling’s plays an insecure riff off his “Crazy, Stupid, Love” persona, while a predictably committed Bale uses his brief screentime as an endearingly, sage-like soothsayer. A supporting cast of Hamish Linklater, Rafe Spall, Melissa Leo, Tracy Letts, and Karen Gillan all waver in effectiveness, but the entire cast links up well with few dull spots.

This is essentially an introduction for McKay as a dramatic director, and tonally his transition to a more controlled hand from the broad comedy seen in “Anchorman” or “The Other Guys” happens mid-film. Beforehand, a few gags or overly mannered characters don’t land, a dramatic beat doesn’t quite hit; however, once the early growing pains pass we’re locked into a solid God’s Eye groove, surveying the runaway banks as their bosses continue as normal and a few choice individuals lose their minds. It’s a supremely incensing affair as it enters its third act, with McKay even indulging a quick, bitter “What If?” catharsis, but “The Big Short” ends up an energetic, absorbing version of these events, marked deeply by its director’s uniquely surreal vision. [B+]